Crazy Eddie wrote:
Significantly, it doesn't have to be a solid "bukcet" to encompass the asteroid. A collapsible cage that expands to the size of the asteroid and then contracts again to the smallest size it can would solve that problem and give the tug something nice and solid to attach its cables too. In that case, figuring out how to keep the cage intact becomes a different engineering problem than the otherwise GEOLOGICAL problem of finding a piece of the asteroid solid enough to stick an anchor. The nice thing about the anchor method, however, is that you still have options to redeploy to a different spot if one of the anchors breaks loose.
USA just posted a story on NASA's lasso mission ( link
) which has a video that's much more informative than the text.
It looks like they're using an expandable bucket for the capture phase (perhaps inflating like an air mattress, but I'm not exactly sure), and then they collapse it tightly around the asteroid. That part looked kind of like sucking air out of bag (which of course doesn't work in a vacuum). It also looked like they were about to start pulling it as you suggest, but they pushed it instead.
Pushing with the remains of an inflatable bag in between the asteroid and the satellite seems to me like perhaps the worst of both ideas
- unless there's some sort of fairly rigid structure in between.
Finally the asteroid is placed in lunar orbit, astronauts fly up on SLS/Orion, dock, spacewalk to the asteroid, and then based on the theme music discover some sort of alien artifact.
Anyway, I recently red that some small chondrites are something between 30% and 50% void space internally, just a loose assemblage of boulders that happen to cling together. That might make any attempt at anchoring both easier (just stick a long pole in a hole or gap) and harder (It might just pull a couple rocks loose). One the other hand it might make processing easier because the material would already be in more manageable chunks.